Is a leukocyte count of 15 in urine abnormal for a male?

Interpretation of Leukocytes in Urine for Males

A leukocyte count of 15 in urine is abnormal for a male and warrants further evaluation for a possible urinary tract infection, especially if accompanied by symptoms.

Normal Values and Interpretation

• According to clinical guidelines, significant pyuria is defined as ≥10 white blood cells/mm³ on an "enhanced urinalysis" or ≥5 white blood cells per high power field on a centrifuged specimen 1
• A leukocyte count of 15 exceeds these thresholds and is considered abnormal
• In males, pyuria is more specific for UTI than in females due to lower rates of contamination and asymptomatic bacteriuria

Diagnostic Considerations

Significance of Leukocytes in Urine

• Pyuria (presence of white blood cells in urine) indicates inflammation in the urinary tract
• The presence of pyuria has high sensitivity (95.6%) but moderate specificity (60.9%) for UTI 2
• Leukocyte esterase testing (which detects enzymes released by WBCs) has approximately 83% sensitivity and 78% specificity for UTI 1

Correlation with Other Findings

• Pyuria alone is not diagnostic of UTI and should be interpreted alongside:
  • Clinical symptoms (dysuria, frequency, urgency)
  • Nitrite test results (highly specific at 98% but less sensitive at 53%) 1
  • Urine culture results (gold standard for diagnosis)

Clinical Algorithm for Males with Pyuria

1. For asymptomatic males with pyuria (15 leukocytes):

   • Do not treat with antibiotics unless the patient has risk factors 1
   • Consider repeat testing to confirm persistence
   • Evaluate for other causes of sterile pyuria (kidney stones, prostatitis)

2. For symptomatic males with pyuria (15 leukocytes):

   • Obtain a properly collected urine specimen for culture
   • Consider empiric antibiotic therapy while awaiting culture results
   • Complete evaluation for anatomic abnormalities if first UTI in adult male

Important Caveats

• The method of urine collection significantly impacts interpretation:

  • Clean-catch specimens are acceptable for most adult males
  • Catheterized specimens may be needed if contamination is suspected

• Laboratory methods affect threshold values:

  • Flow cytometry: >20×10⁶ leukocytes/L is abnormal 3
  • Microscopy: >8 WBC/HPF indicates significant pyuria 4
  • Automated systems: >2 WBC/HPF may be significant 4

• False positives can occur with:

  • Contamination from the urethral meatus
  • Non-infectious inflammation (stones, tumors)
  • Certain medications

Remember that while a leukocyte count of 15 is abnormal, clinical correlation is essential for determining the appropriate management approach.